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Threshold Selection and Resource Allocation for Quantized Identification

作者： jiANG Xiao-yan zhang ji-long ZOU Wei Chang Zhi-yuan

U/U of the environmental sample can indicate the existence of uranium irradiation,and even can be uesd to estimate the burnup of nuclear spent fuel.A study on the burnup estimation of irradiated uranium which was mixed with natural uranium was carried out by measuring the U/U and U/U in the samples by using MC-ICP-MS. According to the equation(1) and(2),a programme for calculating the burnup of the irradiated

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Journal of Systems Science & Complexity 2024年第1期37卷 204-229页

作者： WANG Ying LI Xin ZHAO Yanlong zhang ji-Feng Key Laboratory of Systems and Control Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

This paper is concerned with the optimal threshold selection and resource allocation problems of quantized identification, whose aims are improving identification efficiency under limited resources. Firstly, the first-order asymptotically optimal quantized identification theory is extended to the weak persistent excitation condition. Secondly, the characteristics of time and space complexities are established based on the Cramér-Rao lower bound of quantized systems. On these basis, the optimal selection methods of fixed thresholds and adaptive thresholds are established under aperiodic signals, which answer how to achieve the best efficiency of quantized identification under the same time and space complexity. In addition, based on the principle of maximizing the identification efficiency under a given resource, the optimal resource allocation methods of quantized identification are given for the cases of fixed thresholds and adaptive thresholds, respectively, which show how to balance time and space complexity to realize the best identification efficiency of quantized identification.

关键词： Quantized output resource allocation system identification threshold selection.

Excellent energy storage properties in non-stoichiometric Bi_(0.5)Na_(0.5)TiO_(3)-based relaxor ferroelectric ceramics

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Chinese Chemical Letters 2024年第7期35卷 470-472页

作者： Shunshun jiang ji zhang jing Wang Shan-Tao zhang School of Materials Science and Engineering Nanjing University of Science&TechnologyNanjing 210094China State Key Laboratory of Mechanics and Control of Mechanical Structures College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China National Laboratory of Solid State Microstructures Department of Materials Science and EngineeringCollege of Engineering and Applied Science&Jiangsu Key Laboratory of Artificial Functional Materials&Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China

The rapid development of high-power and pulsed-power techniques inspires extensive investigates on high-performance ceramic-based ***,the low recoverable energy density(Wrec)hampers their wider ***,the non-stoichiometric Bi_(0.5)Na_(0.5)TiO_(3)-based ceramics were designed and *** proper introduction of oxygen vacancies facilitated activating defect dipole,giving rise to reduced remanent ***,the optimal composition exhibited an exceptional high Wrec of 8.3 J/cm^(3),a high efficiency of 85%,and excellent anti-fatigue and thermal *** work provides an efficient approach to explore ceramic capacitors with high capacitive energy storage performances.

关键词： Non-stoichiometric Bi_(0.5)Na_(0.5)TiO_(3) Ceramic capacitor Energy density Thermal stability

UAMP-Based Delay-Doppler Channel Estimation for OTFS Systems

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China Communications 2024年第10期21卷 1-15页

作者： Li Zhongjie Yuan Weijie Guo Qinghua Wu Nan zhang ji Department of Electronic and Electrical Engineering Southern University of Science and TechonologyShenzhen 518055China School of Electrical Computer and Telecommunications EngineeringUniversity of WollongongWollongongNSW 2522Australia School of Integrated Circuits and Electronics Beijing Institute of TechnologyBeijing 100081China School of Mathematics and Statistics Henan University of Science and TechnologyLuoyang 471000China

Orthogonal time frequency space(OTFS)technique, which modulates data symbols in the delayDoppler(DD) domain, presents a potential solution for supporting reliable information transmission in highmobility vehicular networks. In this paper, we study the issues of DD channel estimation for OTFS in the presence of fractional Doppler. We first propose a channel estimation algorithm with both low complexity and high accuracy based on the unitary approximate message passing(UAMP), which exploits the structured sparsity of the effective DD domain channel using hidden Markov model(HMM). The empirical state evolution(SE) analysis is then leveraged to predict the performance of our proposed algorithm. To refine the hyperparameters in the proposed algorithm,we derive the update criterion for the hyperparameters through the expectation-maximization(EM) algorithm. Finally, Our simulation results demonstrate that our proposed algorithm can achieve a significant gain over various baseline schemes.

关键词： channel estimation hidden Markov model(HMM) orthogonal time frequency space(OTFS) unitary approximate message passing(UAMP)

Monitoring seismicity in the southern Sichuan Basin using a machine learning workflow

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Earthquake Research Advances 2024年第1期4卷 59-66页

作者： Kang Wang jie zhang ji zhang zhangyu Wang Huiyu Zhu School of Earth and Space Sciences University of Science and Technology of ChinaHefei230026China

Monitoring seismicity in real time provides significant benefits for timely earthquake warning and *** this study,we propose an automatic workflow based on machine learning(ML)to monitor seismicity in the southern Sichuan Basin of *** workflow includes coherent event detection,phase picking,and earthquake location using three-component data from a seismic *** combining Phase Net,we develop an ML-based earthquake location model called Phase Loc,to conduct real-time monitoring of the local *** approach allows us to use synthetic samples covering the entire study area to train Phase Loc,addressing the problems of insufficient data samples,imbalanced data distribution,and unreliable labels when training with observed *** apply the trained model to observed data recorded in the southern Sichuan Basin,China,between September 2018 and March *** results show that the average differences in latitude,longitude,and depth are 5.7 km,6.1 km,and 2 km,respectively,compared to the reference *** Loc combines all available phase information to make fast and reliable predictions,even if only a few phases are detected and *** proposed workflow may help real-time seismic monitoring in other regions as well.

关键词： Earthquake monitoring Machine learning Local seismicity Gaussian waveform Sparse stations

An envelope-based machine learning workflow for locating earthquakes in the southern Sichuan Basin

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Earthquake Research Advances 2024年第2期4卷 45-54页

作者： Kang Wang jie zhang ji zhang zhangyu Wang Ziyu Li School of Earth and Space Sciences University of Science and Technology of ChinaHefei230026China

The development of machine learning technology enables more robust real-time earthquake monitoring through automated implementations. However, the application of machine learning to earthquake location problems faces challenges in regions with limited available training data. To address the issues of sparse event distribution and inaccurate ground truth in historical seismic datasets, we expand the training dataset by using a large number of synthetic envelopes that closely resemble real data and build an earthquake location model named ENVloc. We propose an envelope-based machine learning workflow for simultaneously determining earthquake location and origin time. The method eliminates the need for phase picking and avoids the accumulation of location errors resulting from inaccurate picking results. In practical application, ENVloc is applied to several data intercepted at different starting points. We take the starting point of the time window corresponding to the highest prediction probability value as the origin time and save the predicted result as the earthquake location. We apply ENVloc to observed data acquired in the southern Sichuan Basin, China, between September 2018 and March 2019. The results show that the average difference with the catalog in latitude, longitude, depth, and origin time is 0.02°,0.02°, 2 km, and 1.25 s, respectively. These suggest that our envelope-based method provides an efficient and robust way to locate earthquakes without phase picking, and can be used in earthquake monitoring in near-real time.

关键词： Waveform envelope Earthquake location Local seismicity Synthetic data Sparse stations

Five quinolizidine alkaloids with anti-tobacco mosaic virus activities from two species of Sophora

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Chinese Chemical Letters 2024年第6期35卷 380-384页

作者： ji zhang Tong zhang Qiao An Peng zhang Cai-Yan Tian Chun-Mao Yuan Ping Yi Zhan-Xing Hu Xiao-jiang Hao State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical UniversityGuiyang 550014China Natural Products Research Center of Guizhou Province Guiyang 550014China School of Pharmaceutical Sciences Guizhou Medical UniversityGuiyang 550025China School of Pharmacy Guizhou University of Traditional Chinese MedicineGuiyang 550025China State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of ScienceKunming 650201China Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical SciencesKunming 650201China

Three novel matrine-type alkaloids(1-3)and two unprecedented aloperine-type alkaloids(4 and 5)were isolated from the root of Sophora tonkinensis and the seeds of Sophora alopecuroides ***,compound 1 possessed an unprecedented 6/5/6 tricyclic skeleton,while compounds 2 and 3 characterized by rare 6/6/5/6 tetracyclic system and 6/6/6/6/6 pentacyclic system ***,compound 4 possessed an unprecedented 6/7/6/6 tetracyclic core,and compound 5 characterized by rare 6/6/6/6tetracyclic *** structures were elucidated by comprehensive spectroscopic data analysis and electronic circular dichroism(ECD)*** tests indicated that compound 5 displayed significant anti-tobacco mosaic virus(TMV)activity compared with the positive control ningnanmycin.

关键词： Matrine-type alkaloids Aloperine-type alkaloids Sophora tonkinensis Sophora alopecuroides Anti-tobacco mosaic virus

Monotropein Induced Apoptosis and Suppressed Cell Cycle Progression in Colorectal Cancer Cells

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Chinese Journal of Integrative Medicine 2024年第1期30卷 25-33页

作者： GAO Quan LI Lin zhang Qi-man SHENG Qin-song zhang ji-liang jiN Li-jun SHANG Rui-yan School of Pharmacy and Department of Medical Oncology the Affiliated Hospital of Hangzhou Normal UniversityHangzhou Normal UniversityHangzhou(311121)China Key Laboratory of Elemene Class Anti-Cancer Chinese Medicines Engineering Laboratory of Development and Application of Traditional Chinese MedicinesCollaborative Innovation Center of Traditional Chinese Medicines of Zhejiang ProvinceHangzhou Normal UniversityHangzhou(311121)China Department of Colorectal Surgery the First Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhouChina Beijing Tong Ren Tang Chinese Medicine Co. Ltd.Beijing(100000)China Department of Traditional Chinese Medicine Hangzhou Shangcheng District People's HospitalHangzhou(310006)China Department of Gynecology Hangzhou Women's HospitalHangzhou(310008)China

Objective: To determine whether monotropein has an anticancer effect and explore its potential mechanisms against colorectal cancer(CRC) through network pharmacology and molecular docking combined with experimental verification. Methods: Network pharmacology and molecular docking were used to predict potential targets of monotropein against CRC. Cell counting kit assay, plate monoclonal assay and microscopic observation were used to investigate the antiproliferative effects of monotropein on CRC cells HCT116, HT29 and LoVo. Flow cytometry and scratch assay were used to analyze apoptosis and cell cycle, as well as cell migration, respectively in HCT116, HT29, and LoVo cells. Western blotting was used to detect the expression of proteins related to apoptosis, cell cycle, and cell migration, and the expression of proteins key to the Akt pathway. Results: The Gene Ontology and Reactome enrichment analyses indicated that the anticancer potential of monotropein against CRC might be involved in multiple cancer-related signaling pathways. Among these pathways, RAC-beta serine/threonine-protein kinase(Akt1, Akt2), cyclin-dependent kinase 6(CDK6), matrix metalloproteinase-9(MMP9), epidermal growth factor receptor(EGFR), cell division control protein 42 homolog(CDC42) were shown as the potential anticancer targets of monotropein against CRC. Molecular docking suggested that monotropein may interact with the 6 targets(Akt1, Akt2, CDK6, MMP9, EGFR, CDC42). Subsequently, cell activity of HCT116, HT29 and LoVo cell lines were significantly suppressed by monotropein(P<0.05). Furthermore, our research revealed that monotropein induced cell apoptosis by inhibiting Bcl-2 and increasing Bax, induced G_1–S cycle arrest in colorectal cancer by decreasing the expressions of CyclinD1, CDK4 and CDK6, inhibited cell migration by suppressing the expressions of CDC42 and MMP9(P<0.05), and might play an anticancer role through Akt signaling pathway. Conclusions: Monotropein exerts its antitumor

关键词： monotropein Chinese medicine anticancer activity colorectal cancer cells network pharmacology

Effects of Co and Nb on the Crack of Additive Manufacturing Nickel-Based Superalloys

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Acta Metallurgica Sinica(English Letters) 2024年第9期37卷 1601-1610页

作者： Kejie Tan jinli Xie Hailong Qin Bin Xu Guichen Hou jinguo Li Zhongnan Bi ji zhang Beijing Key Laboratory of Advanced High Temperature Materials Central Iron&Steel Research InstituteBeijing100081China Beijing GAONA Materials&Technology Co. LTDBeijing100081China Superalloys Division Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

Increasing the print quality is the critical requirement for the additive manufactured complex part of aero-engines of nickel-based superalloys.A study of the effects of Co and Nb on the crack is performed focusing on the selective laser melting(SLM)nickel-based *** this paper,the solvus temperature of γ',crack characteristics,microstructure,thermal expansion,and mechanical properties of SLM nickel-based superalloy are investigated by varying the content of Co and *** alloy with 15Co/0Nb shows the highest comprehensive *** increases the crack risk and thermal deformation,and then Co accelerates the stress ***,Co is an extremely important alloying element for improving the quality of SLM nickel-based ***,the crack growth kinetics and the strain difference are discussed to reveal the SLM crack regular that is affected by time or *** analysis work on the effect of alloying elements can obtain an effective foundational theory to guide the composition optimization of SLM nickel-based superalloys.

关键词： Nickel-based superalloys Selective laser melting Element effect Crack

Stability in Inverse Problem of Determining Two Parameters for the Moore-Gibson-Thompson Equation with Memory Terms

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Journal of Systems Science & Complexity 2024年

作者： FU Songren CHEN Liangbiao zhang ji-Feng Key Laboratory of Systems and Control Academy of Mathematics and Systems Science Chinese Academy ofSciences School of Automation and Electrical Engineering Zhongyuan University of Technology Key Laboratory of Systems and Control Academy of Mathematics and Systems Science ChineseAcademy of Sciences

In this paper, the authors consider the inverse problem for the Moore-Gibson-Thompson equation with a memory term and variable diffusivity, which introduce a sort of delay in the dynamics,producing nonlocal effects in time. The H¨older stability of simultaneously determining the spatially varying viscosity coefficient and the source term is obtained by means of the key pointwise Carleman estimate for the Moore-Gibson-Thompson equation. For the sake of generality in mathematical tools,the analysis of this paper is discussed within the framework of Riemannian geometry.

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